Abstract: A holder for holding a plurality of position sensors, such as ultrasonic position sensors, in a ganged array for pivotal movement about a vertical pivot axis passing through the holder. The holder includes a pair of housings carried on a rotatable shaft, each housing carrying six sensors in two groups of three. Each group is angularly offset from the other group. The sensors within a group are angularly offset from each other by angles that are multiples of the beam angle of the sensor beams.

Abstract: A reversible drive for a fish-finder apparatus includes a motor, a drive gear driven by the motor, a driven gear driven by the drive gear and a fish-finder drive shaft driven by the driven gear. The drive gear contains one or more actuator members which actuate a drive control member, such as a reverse polarity switch, during rotation of the drive gear. When actuated, the drive control member reverses the drive to the motor and thereby reverses the drive to the fish-finder. A display panel contains diode indicators which are illuminated in response to the movement of the fish-finder.

Abstract: A sonar system for arctic seafloor reconnaissance has a pair of transducers affixed to a holder so as to form a transducer array. A vertically extended tube assembly rotatably supported by a tripod suspends this transducer array at a specified depth in water such that the transducer array is tilted at a specified tilting angle and oriented in a specified azimuthal direction. One of the transducers is made to emit directional acoustic signals and the reflected acoustic signals received by both of the transducers are converted into electrical signals. These signals are processed together with signals indicative of the tilting angle and the orientation of the transducer array to obtain seafloor imagery and depth data.

Abstract: The invention relates to a simple, cheap sonar system with high image rate, for the detection of objects and the imaging of sea bottoms. It consists in transmitting n uncorrelated successive codes in a sector of angular width exactly equal to n times the angular width of the reception sector .theta..sub.R, the reception antenna continuing to turn during this time whilst the first signal transmitted has not yet reached the maximum range dmax, and in receiving, in the sector of angular width .theta..sub.R, the echoes of these n codes, coming from n propagation regions which are adjacent in relation to the reception axis, and lying between 0 and dmax in space, each of them having a depth equal to dmax/n.

Abstract: Improved apparatus and method are provided for locating and mapping sediment in a container, which is at least partially filled with liquid. A sonar transducer is mounted with the container for emitting acoustic energy into the liquid and for receiving reflected acoustic energy. The sonar transducer is rotatable about mutually perpendicular first and second axes to provide a dual-axis capability. The transducer is controlled to emit discrete acoustic signals and receive reflected acoustic signals along discrete scanning axes at each rotational position in a predetermined sequence of rotational positions. The distance between the transducer and a corresponding point of reflection along each scanning axis is compared to a predetermined reference distance along the corresponding scanning axis. The reference distance represents the distance between the transducer and an inner surface of the container along the corresponding scanning axis.

Abstract: Ultrasonic energy is emitted within a detection envelope from a single transducer and echoes of targets therein are received during scanning displacement of the transducer through a predetermined sweep angle from a zero position on a platform, against the centering bias of springs through which pulse signal current is conducted to and from the transducer. An electromagnetic scanner drive imparts oscillatory motion to the transducer by magnetic generation of displacing forces varied in accordance with its loading at the zero position of the transducer and at limit positions detected by a position sensor to maintain a constant scanning sweep angle in timed relation to pulsing of the transducer through a transmit-receive circuit under preprogrammed computer control.

Abstract: A sonar system which insonifies a target area in a plurality of distinct and separated insonified regions as a result of an acoustic transmission and thereafter fills in the blank regions upon subsequent transmissions, with each transmission always leaving a space between insonified regions, which is filled in by a subsequent transmission or transmissions.

Abstract: Two submerged rotatable sets of transmitting and receiving transducers are ongitudinally spaced along the side of a river to establish intersecting lateral sonar beams obliquely oriented at opposing 45.degree. angles relative to the primary river current. Each beam can be slewed in opposite directions through 45.degree. to parallel orientation with the current. The outputs of the transducer arrays are passed to respective doppler sonar detection units which produce alarm output signals when the normalized doppler frequency shift within at least one of a plurality of narrow frequency bands in each unit exceeds a predetermined level. The transmitting frequency of each array is varied with rotation of the array. If only one beam detects a target, a control circuit causes the other beam to slew until it acquires the target. With detection by both beams, the position of the target can be computed from the bearing angles of the arrays.

Abstract: Universal directional orientation of the vibratory sensing face of a transducer is achieved by mounting the transducer on horizontal axles journaled by surrounding sleeves mounted on the depending end of a vertical standard attached to a moving carrier. The sleeves and axles are interconnected with manual controls by links and universal joints at the end portions of the standard. Manual controls are located at the upper limit of the standard for disposing the transducer in selected directions by control links extending between the manual controls and the universal joint controlled mounting of the transducer at the depending end portion of the standard.

Abstract: An ultrasonic distance sensor generates ultrasonic waves and transmit same toward a target surface, the distance to which is to be measured, through a predetermined path. The sensor is also provided with a reference surface which reflects ultrasonic waves, which reference surface is disposed within the aforementioned predetermined path of the ultrasonic waves. A receiver associated with delayed pulse generators receives the ultrasonic waves reflected by the reference surface or by the target surface, selectively. Arithmetic operations based on the elapsed time between transmission of the ultrasonic waves and reception of the ultrasonic waves from the reference surface derive the transmission velocity of the ultrasonic wave based on the known distance to the reference surface. On the basis of the derived transmission velocity and the elapsed time measured with respect to the ultrasonic waves reflected by the target surface, the distance to the target surface is derived.

Abstract: The received signal from an acoustic echo detection and ranging system is mpared with internally generated signals indicating the focus of a variable focus transducer. Logic circuits in the signal comparison channel develop control voltages to focus said transducer upon a predetermined area from which said received signal originates.

Abstract: Images of underwater features, animate and inanimate, are produced from substantial distances in any direction around a boat, using small and easily mountable sonar devices, including three sonar transducers, two being stationary and the third being directable, the transducers being operable at various ultrasonic frequencies. Under keyboard control and using completely integrated electronic circuitry, images and echo sounding reports are generated on a graphic video display. The images include a sector-shaped image from a sector scan which covers a selected range of azimuth angles at a selected down angle.

Abstract: A positionable transducer array on a stationary platform proximate a layered site on the seabed coherently insonifies locations at the site with a signal having a selected power, resultant center frequency, beamwidth, bandwidth, shape and incident angle. A positionable receiver array on the platform captures the return signals. Sub-surface acoustical properties of the location are then predicted from the return signals and a calculation of the speed of sound in water at the site. Subsequent locations at the site are then interrogated and an interpolation is made of acoustical properties between locations to develop a model of the acoustical properties at the site.

Abstract: A sensor apparatus for detecting sludge in a tank e.g. an oil storage tank, wherein sonar tarnsmission and reception is effected by a transducer (29) whose acoustic center is coincident with the center of curvature of a liquid filled part spherical sonar dome part (15) of a housing (13) for the apparatus. The acoustic pressure waves consequently pass through the dome part of the housing in a direction normal to its surfaces thus minimizing velocity, amplitude and phase changes of the waves as they pass to and from the transducer, and avoiding blind spots in the area monitoried by sensor apparatus. Preferably, the apparatus further includes an arrangement (31, 33, 35, 37) within the housing for angularly moving the transducer (29) about two orthogonal axes which intersect at said center of curvature.

Abstract: A sonar system for a water craft including a transducer assembly mounted to the hull of the water craft, and a control circuit for applying signals to the transducer for forward transmission by the transducer and for sensing signals reflected from objects forwardly of the craft and for causing actuation of an alarm. The transducer assembly is mounted for pivotal movement relative to the hull such that during pitching motion of the craft, the signals transmitted by the transducer remain in a horizontal plane.

Abstract: A contact ultrasonic transducer head assembly. A stationary housing is adapted to be fitted to a remotely operated manipulator. A movable assembly slidably received by the stationary housing has a plurality of independently suspended ultrasonic transducers mounted thereon. A position encoder mounted in the movable assembly monitors movement within the stationary housing. A limit switch is used to electrically disable the remotely operated manipulator when the movable assembly slides a predetermined distance into the stationary housing to prevent damage to the transducers or the surface being inspected.

Abstract: A three-dimensional ultrasonic position control device suitable for controlling computer displays or robot movements is disclosed.More specifically, signals from an ultrasonic transmitter are received by multiple receivers. The received signals are processed by a processing circuit which provides signals to a computer system for use in controlling a computer display or a robot. This system is particularly adapted to use inexpensive components to provide for a low cost mass producible control device.

Abstract: A method of imaging an object by the ultrasonic or electromagnetic wave by mechanically or electronically scanning the ultrasonic or electromagnetic wave transmitting/receiving system to transmit the ultrasonic or electromagnetic wave beam spreading in space of the object and using the trace (TOF locus) from the transmission to the reception while receiving the reflected wave from the object, and sequentially reproducing the line image at the central line of the synthetic aperture range using the received signal group from the scanning points in the synthetic aperture range to sequentially image the area to be imaged while scanning the ultrasonic or electromagnetic wave transmitting/receiving system. An imaging apparatus applied with the method has a relatively simple hardware structure for reproducing the image and is also able to perform the operation in real time.

Abstract: A dual axis transducer assembly comprises a transducer (20), a yoke (24) which mounts the transducer for oscillating movement about a substantially horizontal axis. A turntable (28) mounts the yoke and hence the transducer for oscillating motion about a vertical axis. Separate motors (10) and (12) supply motion to the transducer and control means (84), (86), (88) are employed to control the operation of the motors.

Abstract: A method for the determination and display of signal arrival time, intensity, and direction for use with time domain measurements. The method may be implemented by either hardware or by software and includes obtaining at least four separate time domain measurement, such as energy time curves (ETCs), at ninety degree intervals on a horizontal plane. Opposing ETCs are differenced to obtain X and Y Cartesian components. For display in a polar format to illustrate the direction of arrival the X and Y components are converted into an angular value. The angular value determining the theta angle and either the time of arrival or intensity expressed in X and Y components establish the polar vector length. To display a three dimensional space two more ETCs are obtained in a vertical plane and correlated in the manner described above.

Abstract: In an ultrasonic imaging apparatus of the type having a plurality of selectable modes of operation, a motor-driven electroacoustic transducer is steered in a sector field in a predetermined relation to a selected operational mode. The sector scan format of returning echos is converted to a line-by-line raster display format in response to line sync pulses. The number of line sync pulses generated per unit time interval is scaled by a factor of N/M, so that it corresponds to the number of pulses generated by the encoder during the same time interval, where N and M are integers which are variable as a function of the selected mode. Phase comparison is made between the pulses generated by the encoder and the scaled line sync pulses to generate a phase difference signal from which a speed control signal is derived for controlling the speed of the motor.

Abstract: The present invention provides a method and device for determining the positioning of an element or target using at least one acoustic emitting-receiving sensor. In this method only the signal received by said sensor and due to the diffraction of the signal emitted by said sensor is taken into account.

Abstract: An apparatus and method for achieving variable observations angles by a single transducer rotationally and pivotally mounted with a housing; and for utilizing the variable angle transducer to detect and trace and distance of unseen objects within a casing from the transducer by moving the transducer within its housing which is held stationary against the casing; and for determining the angle of observation between the transducer and the observed object; and thereby accurately determining the relative position and orientation of the object within the casing.

Abstract: An acoustic lens arrangement having at least one transducer for the generation and/or for the reception of a plane acoustic wavefield. The arrangement includes a focusing surface for focusing the acoustic wavefield in an object region and at least one medium for the low-loss transmission of the acoustic wavefield between a transducer, the focusing surface and the object region to be investigated. The longitudinal axis of the focusing surface is inclined relative to the direction of the normal to the acoustic wavefield in such a manner that when the longitudinal axis is positioned normal to the surface of the object region, the acoustic beams incident thereon form a critical angle .theta..sub.R with the normal to the surface of the object.

Abstract: A sonar transducer comprising a stack of an even number of antennae with identical linear networks. The stack is driven by a reciprocating rotary movement of low amplitude, with the antennae alternately emitting and receiving with each half wavelength of the rotary movement. The emitting antennae as well as the receiving antennae are mutually staggered by an angle equal to the angle of rotation of the assembly. The assembly of receiving antennae are staggered with respect to the assembly of emitting antennae by an angle equal to the phase delay of an emission lobe with respect to the corresponding reception lobe.

Abstract: An underwater detection system which has a transmitting and receiving unit for radiating an ultrasonic wave pulse into the water within a narrow sector and receiving echo signals by a plurality of reception beams, and turns the transmitting and receiving unit by a predetermined angle to search another narrow sector each time the search within the narrow sector is completed, thereby searching the water within a wide angular range.

Abstract: Method and apparatus for identifying a number of people in a monitored area wherein a first reflected ultrasonic wave map of the monitored area is collected that includes background objects. A second reflected ultrasonic wave map of the monitored area is collected when people may be present in the monitored area. The first collected background defining map is subtracted from the second collected map to obtain a resulting map. The resulting map is processed to identify clusters having a minimum intensity. A cluster size of the thus identified clusters is utilized to identify clusters corresponding to people. The ultrasonic detecting method and apparatus is utilized with a wave signal receiver for identifying an audience composition of the receiver and determining the viewing habits of the public.

Abstract: A vibration isolation module (30) includes termination members (34, 36) at each end to which are connected electrical wires or cable (39), and a braided rope of aramid fiber (32). A plurality of compliant members (40) of polyurethane hose having tapered ends are inserted at intervals within the braided strands of the rope (32). Some of the compliant members (40) may be filled solid with polyurethane. Variable lengths of hose or variable diameters and wall thicknesses may be used to vary the compliance of the compliant members (40). Between the compliant members (40) are positioned a number of spacer members (38) which provide support for the hose (37) and electrical wires (39). This structure is carried within an oil filled stretchable hose (37) fastened to the termination members. When the module (30) is subjected to forces in tension, the load is carried by the aramid fiber rope (32) which, as the load is increased, tends to squeeze down and compress the compliant members (40).

Abstract: An apparatus for detecting obstructions behind a vehicle, employing ultrasonic waves is disclosed. The apparatus comprises an ultrasonic transmitting and receiving device disposed on the rear portion of the vehicle, an electric motor for rotating the transmitting and receiving device at a constant velocity, an angle sensor for detecting the rotating angle of the transmitting and receiving device and a sonar circuit for emitting ultrasonic waves through the transmitting and receiving device at predetermined rotating angles, receiving ultrasonic waves reflected from obstructions through the transmitting and receiving device at predetermined rotating angles and measuring the distance to the obstructions from the time taken from the transmission to the reception of the ultrasonic waves.

Abstract: Method and apparatus for surveying positions of mooring lines extending between a moored structure and anchors in the water bottom comprising a rotatable submarine transducer assembly including acoustic pulse transmitting means and an array of acoustic receivers, a support for locating the transducer assembly at a predetermined level above the water bottom and actuator means for rotating the assembly about a vertical axis relative to the support. During operation the transmitting means produces a beam of acoustic pulses. Pulse reflections originating from mooring line sections that are successively scanned by the beam are received by the acoustic receivers, and the position of each scanned mooring line section is calculated by a processor unit on the basis of the time interval at which the pulses are received after transmission.

Abstract: A low cost, efficient, ultrasonic transducer and method comprises a narrow beam electrostatic transducer and a beam transformer operated in air for expanding the emitted beam of the electrostatic transducer relative to a single axis. The beam transformer is a sonic reflecting surface spaced from the ultrasonic beam generator and within the near field thereof and having a geometric surface in which all points of said surface are generated by the revolution of a line about a fixed axis which is normal to the plane of the electrostatic transducer. A partial surface of a cone, the axis preferably being offset from the axis of the narrow beam electrostatic transducer and placed in the near field thereof transform the narrow beam to a broad beam with the beam transformer being an effective coupling element for the emitted beam and the return echo for ranging systems which are both efficient and easy to produce and do not have significant alignment problems.

Abstract: Apparatus for measuring and indicating the settlement of the floor of a large liquid containing vessel such as an oil storage tank. The apparatus comprises sonic echo sounding means positioned at or movable between each of a multiplicity of spaced points disposed within the vessel and above its floor in known relationship one with another, and ranging means for furnishing for each point, and upon the basis of the echo sounding means output, a measure of the distance from the point to the vessel floor and an indicator (preferably visual) for indicating from the ranging results the settlement of the floor below those points. In preferred embodiments, the surface of the liquid within the vessel is utilized as a datum and the arrangement may be adapted to provide an indication of the volume of liquid within the vessel.

Abstract: A multielement acoustic transducer comprising a metal plating which is formed by plating the convex surface of a low-melting metal having a plurality of convex semispherical holes and then fusing and removing the low-melting metal, the metal plating being used as a base electrode, a piezoelectric material which is formed on the base electrode, and a top electrode which is formed on the piezoelectric material, the piezoelectric material functioning as concave transducer elements.

Abstract: Apparatus for remotely controlling the horizontal and vertical direction of a pendulously suspended transducer by means of concentric generally vertical control shafts is disclosed. A frame in which the transducer is mounted for rotation about a tilt axis is pendulously suspended from one control shaft. The other control shaft is rotatably coupled through a universal joint to a first pulley mounted in the frame for rotation about a vertical axis. The first pulley is rotatably coupled to a second pulley mounted on the transducer for rotation therewith about the tilt axis by means of a cable routed over guide pulleys which change cable direction.

Abstract: A Scanning Sonar Display System comprised of a TV monitor, a scanning mechanism with transducer, control logic with image memory and timing, a power source such as a 12 volt storage battery and a set of operator controls. The type of TV monitor used is well known and similar to those used by raster scan computer terminals. The scanning mechanism has a stepping motor with a 10 to 1 reduction cable drive system to rotate the transducer with home initializing contacts. The control logic includes two counters used as image memory address registers. The first, the refresh counter, is used for reading the image memory during refresh and for determining the horizontal and vertical sync for the TV monitor. The second, the entry counter, is used for writing sonar and depth data into the image memory and is also used for control of the stepping motor. Home initializing contacts are used to initialize this counter.

Abstract: The present invention is directed to a detection system which forms reception beams successively in a series of angular directions. The detection system comprises receiving means for receiving incoming signals in such a manner that the frequency of the incoming signals is varied in accordance with the Doppler effect, and a matched filter for pulse-compressing output signals from said receiving means, with output signals from said matched filter being displayed in an indicator.

Abstract: The reflector of an acoustic echo ranging system is matched so as to make up for the influence of the temperature at the bottom of the reflector, on the measurement of the back-reflected signal. The acoustic signal receiver being stationary the transmission frequency is controlled by a temperature responsive electronic circuit so that the receiver is always located at the same pressure antinode. Alternatively, the transmission frequency being fixed, the position of the receiver is controlled by a temperature responsive mechanical gear causing the position of the receiver to coincide with the same pressure antinode.

Abstract: An imaging sonar system is disclosed comprising a transmitter, a receiver, and a rotatable transducer coupled with the transmitter and receiver for generating sound waves and for detecting echoes therefrom. Drive means are provided for rotating the rotatable transducer. Transducer position sensing means are provided for sensing the rotary position of the transducer. Analog to digital converter means are coupled with the receiver for converting receiver emitted signals into digital form. Serial access memory means are provided entering into storage receiver emitted signal data in digital form at a preselected rate and for withdrawing from storage receiver emitted signal data at a rate different than the predetermined rate. Write and read control means are also provided for respectively entering digital data into and recalling digital data from the memory.

Abstract: A method, a device and a transducer for dimensional measurement of objects by means of ultrasonics, where the objects are carried past at least an ultrasonic measuring device consisting of a combined transmitter/receiver or separate transmitter/receiver. The reflected ultrasonic signals are used to determine characteristic three-dimensional dimensions of the objects. Said device or devices are arranged either such that the ultrasonic beam or beams therefrom are provided with a reciprocating movement which substantially crosses the direction of movement of the objects or by letting the ultrasonic beam or beams therefrom be stationary. The delay of the reflected signals is used to form a three dimensional image of the object by means of a computer, said image being compared with known images for identification. The ultra sonic measuring device has a narrow, substantially rotation-symmetric radiation diagram.

Abstract: A housing for an electroacoustic transducer includes a filling or access port for introducing an inert liquid into the chamber defined by the housing. The access port includes a bubble trap and a vent for extracting gaseous bubbles from the fluid fill. The structure of the access port also comprises a substantially zero spring pressure expansion cavity for the fluid.

Abstract: A housing for an acoustic transducer includes means for dispersing internal reflections within the housing to minimize the incidence of such internally reflected acoustic pulses on the transducer itself, thereby avoiding the generation of spurious electrical signals for transmission to the translating circuitry.

Abstract: An electronic depth finder apparatus is shown for use in fishing and/or navigation, and it includes a combined impulse control means and read-out, as well as a remote cooperating transducer immersed in the water. The invention relates to a means of adjustably mounting the transducer on a boat so that the transducer may be capable of as many as three planes of movement; namely, swinging movement in a vertical plane, unlimited rotational movement in a horizontal plane about a vertical axis, and up and down vertical movement between a lower "searching" position and an upper "running" position. The upper "running" position allows operation of the apparatus when the boat is moving at high speeds.